Metal zirconium that is a material of a zircaloy alloy used in a cladding tube or a channel box (CB) for an atomic fuel is produced by removing impurities such as homologous element hafnium or the like from zirconium oxide called zircon sand.
As a method of producing metal zirconium, a chlorination-volatilization method where zirconium oxide containing hafnium is converted to chlorides and hafnium is separated from zirconium by vapor pressure difference between the chlorides is disclosed in U.S. Pat. No. 6,929,786 (Patent Document 1).
Furthermore, as a method of producing metal zirconium, a method where zirconium oxide is once converted to an oxychloride, followed by dissolving in hydrochloric acid, further followed by conducting solvent extraction to separate hafnium from zirconium is disclosed in U.S. Pat. No. 5,762,890 (Patent Document 2).
In Patent Document 2 described above, as a method of producing metal zirconium from a purified zirconium oxychloride from which hafnium has been separated, a method where a zirconium oxychloride is once converted to a zirconium oxide, followed by converting to a chloride, and a Kroll process is used to produce metal zirconium is disclosed.    Patent Document 1: U.S. Pat. No. 6,929,786    Patent Document 2: U.S. Pat. No. 5,762,890